Method of making holdover refrigeration plates



o. s. MOGUFFEY 2,416,015 MBTHODOF MAKING HOLD'OVER REFRIGERATIOK PLATES Film Feb. s, 1943 '2 Sheets-Sheet 1 F/Q-i mvsmox.

0/970 5. MC awn-5) Patented Feb. 18, 1947 UNITED STATES PATENT OFFICE METHOD or HOLDOVER v REFRIGERATION PLATES Orton s. McGulfey, Lansing, Mica, asslgnor re Kold -flold Manufacturing Compan'y, -IJansing, Micln, a corporation of Michigan I Application February 6, 1943, Serial No. 474,949

Claims. (o1. .62170) This invention relates to hold-over refrigeration plates and more particularly'to a-novel construction and method of making such plates.

Hold-over refrigeration plates conventionally comprise a sealed tank containing a refrigerant evaporator coil and being partially filled with a The evaporator coil liquid hold-over solution. is adapted to be connected to a refrigerant condensing unit for a period long enough to freeze or congeal the hold-over solution. The evaporator is then disconnected from the condensing unit and the hold-over frigerating effect.

solution itself produces a re- One of the problems which is encountered in a the use of such plates is the rupturing of the tank when the hold-over solution freezes and expands. This problem has been partially'overcome in the pastby filling the tank only partially full of liquid and then exhausting the air in the remainder of the tank to create a vacuum space into which the hold-over solution can expand when it freezes. This results in a slopping around of the solution'when it is in the liquid state and an unequal distribution of the refrigerating effect throughout the surface of the plate.

All of the foregoing disadvantages are overcome by the present invention which provides a tank which is, in effect, completely filled with the hold-over solution in its liquid state and l which nevertheless is capable of sufilcient expansion to accommodate the frozen solution without rupturing the tank.

This novel result is obtained by filling the tank completely full of liquid solution which tends to bulge the sides outwardly, then pressing the sides 7 inwardly to expel a portion of the liquid and any trapped air, next sealing the tank while pressure is still being exerted against the side walls, and finally releasing the pressure from the side walls.

This method apparently produces a condition where the pressure within the tank is less than the pressure of the atmosphere and the latter holds the side walls of the tank in the predetermined position which they occupied during the sealing operation. When the hold-over solution freezes, and thereby expands, the side walls of the tank are caused to bulge out from their normal condition to some extent, But when the hold-over solution melts and returns to the liquid r 2 .7 state, the tank contract-s again. Thus, thetank is ineffect completely filled with hold-over solution at all times.

For a more complete understanding of the invention, its objects and advantages, reference ould now be had to the accompanying drawings, wherein- 'Figure 1 is 'a side view, partly in section of a refrigeration plateembodying the present invention; 7 t

Figure 2 is a sectional view taken on substantially the line 2-4 of Figure 1;

Figure 3 is a topplan view of the plate and the means employed for pressing the sides of the tank inwardly before sealing;

Figure 4 is a sectional view taken on the line 4-1 of Figure 3 illustrating how the tank is filled;

Figure 5 is an enlarged fragmentary view of the structure shown in Figure 4; and

Figure 6 is a. pictorial view of one of the fins for spacing the evaporator coil and the walls of the tank.

As shown in Figures 1 and 2, the refrigeration plate comprises a tank l0 consisting of two complem'enta'ry pan like sheet metal stampings welded to each other about their peripheries. Within the tank there is disposed a refrigerant evaporator coil H having associated therewith a plurality of fins 12 which serve as heat transfer means and also as spacers interposed between the opposite side walls of the tank. The fins I2 are of U-shape in cross-section, comprising web portions I'Zd'and flanges l2b. The fins are arranged in pairs on opposite sides of the evaporator coil with the web portion of each fin formed to partially surround the coil.

The evaporator coil is provided with suitable inlet and outlet connections l3 and I4 exteriorly with a plurality of small openings I5a just inside of the wall of the tank In which serve as bleeder openings for air and liquid hold-over solution, as will appear more fully hereinafter.

It will be understood from the foregoing that the evaporator coil I I and fins I2 are assembled together and the tank I is then formed around them by welding the adjacent edges of the sheet metal stampings together. The spud I and the connections I3 and I4 are preferably installed on the appropriatesheet metal blank before the tank is formed. y

Afterthetank has-, been formed, it is placed upon the support shown in Figures 3 and 4 for filling, compressing and sealing. This structure comprises a base or immovable lower supporting member l6 and an upper and movableclamping member I! having one edge hingedly' connected to the'support I6 and with; its, opposite edge 7 formed to be detachabiy clampedjtothe,support I6. The members I6 and I1 are ,of a size to substantially enclose the tank I0 when it is positioned therebetween.

The base I6 provides an inclined support;

Mountedupon' the support is a tank I8 which is identical to tank-I0 but. does not have anything inside of it. An air hose I9 is connected tothe filler opening of tank mo that when'airiis forced into the tank it serves as a pressure bellows. Mounted on top of tank I8 is an assembly comprising a sheetpf plywood 20,, a sheet of sponge rubber 2I, and a sheet of relatively hard and firm rubber 22. V i The tank lll ispla'ced u'pon the sheet of rubber 22 with the spud l5'constituting the filler opening located at theupper end of the inclined support. g H

The movable support member .II, comprises a sheet of metal 2'3'having secured to the under surface thereof; in" the order named, a sheet of plywood 24, a sheet ofspo'nge rubber "25, and a sheet of hard rubber, 25. Thus,'when the'parts are in the position shown in Figure '4, the tank I0 is located between thesheets of hard rubber 22and26.

As previously mentioned, one edge of the movable support member IT is connected to one edge of the stationary support member" I6 by hinges 21. A clamp 28 is adapted to detachably connect the other edges of the two support members to- I gether. It will be understood thatthe movable member can be swung toanl upright position to permit the installation or 'removalof the tank l0.

s In practice, a tank I0 is placed in'the support as shown in Figure 4 and the'movable member I'I clamped to the stationary member l6 before any pressure is applied to bellows I8 and before any liquid hold over solution is introduced into tank Ill. As soon as that has beendone, liquid holdover solution is introduced into tank In through the spud l5 by means of a special funnel 29.

As the tank fills up with liquid the Side walls tend to bulge outwardly against the rubber cushions. When it is completely filled, air is forced into bellows I8 under sufficient pressure to cause the side walls of tank ID to press snugly against the fins I2. This forces apart of the liquid hold over solution out of the tank and an overflow pipe is associated with the funnel 29 to carry it away. a i

Overflowplpe 30 has one end attached to the inside of funnel 29 ,and terminates at thesame level'as bleeder openings I511 formed in the spud I5. Thus, the liquid which is forced out .of the tank lliby the bellows I8 passes through openings I5a and is drained away through siphoning action by overflow pipe 30, leaving the tank still in effect completely filled with liquid. While the tank is still in that condition and under the influence of the expanded bellows i8, the funnel 29 is removed from the spud i5 and a plug 3i is threaded into the spud I5 so as to completely fill the space within the spud which is not occupied by liquid hold-over.

The plug 3| seals the filler opening and the entire tank I II is then hermetically sealed. After that has been done, the pressure is. withdrawn from bellows I8, the movable member I1 is swung to an upright position, and the tank I0 is removed from the support ready for use as a hold-over refrigeration plate, The support is then ready to receive another tank I0.

' -When the tank I0 has been completed as above described, the side walls thereof will remain in 20 contact-with theflns I2 throughout their entire areas so long as the hold-over solution remains in a liquid state. When the solution is frozen and expands, the side walls of tank I0 bulge away from the fins I2 and accommodate themselves to the enlarged volume of the hold-over solution without rupturing. As shown, in order to obtain this, advantageous result it is essential that the side walls of the tank be of relatively large area. In order to prevent localization of the bulging at the edges of'the tank which might result in rupturing the tank, it is desirable to utilize the arrangement described in my recently issued Patent No. 2,287,941 issued June 30, 1942.

Thescope of the invention is indicated in the appended claims.

1 claim: 1. The method of making hold-over refrigeration plates which comprises providing a tank having opposed side walls of relatively large area and having ajiiller opening adjacent one edge .thereof, said tank containing relatively rigid spacer means interposed between the side walls, positioning said tank with the filler opening lo- "cated above the remainder of the tank, introducing, liquid into the tank through said filler opening until the tank is completely filled, applying external pressure against, the side walls of the tank to press the side wall into engagement with the spacer means, sealing the tank from the atmosphere while the tank is under the influence ofsaid external pressure, and thereafter releasing the pressure from the side walls.

2. The method defined in claim 1 wherein the external pressure applied to the side walls is distributed substantially uniformly over the side walls of the tank.

3. The method defined in claim 1 wherein the external pressure is applied to the side walls of the tank through a yieldable medium to distribute to the pressure uniformly;

, 4. The method defined in claim 1 wherein'the external pressure is applied to the side walls by supporting one side of the tank on a relatively immovablesupport andengaging the other side 65 of the tank by a relatively movable clamp and then pressing the movable clamp toward the immovable support.

5. The method of making hold over refrigera- 6 tank through said filler opening until the tank is completely filled, applying external pressure TED AT S PA ENTS against the side walls of the tank to decrease Number Name Date the volume of the tank and expel some liquid 2241411 McGufiey May 13 1941 therefrom, thereafter sealing the tank from the 5 2 2 941 McGufi'ey June 30 1942 atmosphere while the tank is under the influence 2172'311 Thomas Sept 1939 of said external pressure, and finally releasing 2063646 whitesel 1936 the Pressure Said Side Walls- 1880969 Mufily Oct. 4 1942 ORTON MCGUFTEY- 10 2,177,919 Vogt Oct. 21, 1939 2,016,377 Krotzer Oct. 8, 1935 REFERENCES CITED 1,979,517 Heideman Nov. 6, 1934 The following references are of record in the file 01 this patent: 

